1. Field of the Invention
The present invention pertains to a substrate dry cleaning system, and more particularly, pertains to a cluster tool module for dry cleaning of a substrate in a controlled gaseous environment.
2. Description of the Prior Art
There have been many applications of chemistry for surface treatment of silicon and other wafers in the semiconductor industry. The uses of plasma generated ions have been used in the areas of etch and photoresist removal. These methods have been quite useful, but have a disadvantage of potentially causing damage to the substrate and surface layers. The use of aqueous chemicals is the current standard for wafer cleaning.
The emergence of gas based surface preparation techniques offer the "fine tuning" capabilities that are desirable to the vacuum based cluster tools. The processes that use dry gases or high vapor pressure gases are compatible to the vacuum processes. Reactant gases that combine with the intended contaminant form volatile compounds, such as HCL, CL.sub.2, F.sub.2 mixtures, or O.sub.2, which are well known. It is not always desirable to heat the wafer above 200.degree. C. or 300.degree. C. because of the diffusion of impurities into the bulk material of the substrate. Another method of surface preparation is to perform wet chemical treatments.
The present invention provides a cluster tool module for gaseous dry cleaning of substrates.